Renewable energy sources, such as wind turbines, have become a significant contributor to the daily energy supply. Electrical energy generated by wind turbines are fed into AC power grids and thereby distributed to the various energy consumers.
In case of a power grid failure causing a frequency drop a swift power boost may be required in order to stabilise the power grid. It is well-known that such power boosts may be provided by wind turbines being operated in a curtailed mode of operation. Thus, if a number of wind turbines are operated in a curtailed mode of 90% the remaining 10% of power may be boosted into the grid in the event of a grid failure in order to stabilise the grid. However, if the wind turbines are already operated at nominal power levels no extra power is available for grid stabilisation. Moreover, inertia emulation where wind turbines are operated above their nominal power levels for a short period of time may be applied for grid stabilisation.
However, it is generally costly and inefficient to operate wind turbines in a curtailed mode of operation. The reason for this being that curtailed wind turbines are operated below their nominal power ratings. Moreover, the capability of inertia emulation is rather low. The reason for this being that inertia emulation comes at the cost of a rotational speed drop and a power drop after a power boost. Eventually, this may destroy grid stabilization.
It may be seen as an object of embodiments of the present invention to provide an effective and a swift power regulation scheme in order to deliver/absorb power to/from a power grid connected to a wind power facility, such as a wind turbine or a WPP.
It may be seen as a further object of embodiments of the present invention to provide a swift power regulation scheme in order to stabilise a power grid in the event of a grid failure.